The temperature in Houston may be tolerable, but the humidity is probably going to be over 90%. In our three years there the Texas never very close to 100 degrees, but the humidity was a killer, frequently above 95%. Teams from other areas, even in Texas, had a tough time.
Stillwater is bound to be tough. They’ll probably have SLC-type temperatures with humidity over 70%. Incidentally, to get to Stillwater from Oklahoma City, just go north until you smell it, then east until you step in it. That’s what we learned when we moved to Oklahoma City.